Cellular and Humoral Mechanisms Involved in the Control of Tuberculosis

Abstract

Mycobacterium tuberculosis (Mtb) infection is a major international public health problem. One-third of the world's population is thought to have latent tuberculosis, a condition where individuals are infected by the intracellular bacteria without active disease but are at risk for reactivation, if their immune system fails. Here, we discuss the role of nonspecific inflammatory responses mediated by cytokines and chemokines induced by interaction of innate receptors expressed in macrophages and dendritic cells (DCs). We also review current information regarding the importance of several cytokines including IL-17/IL-23 in the development of protective cellular and antibody-mediated protective responses against Mtb and their influence in containment of the infection. Finally, in this paper, emphasis is placed on the mechanisms of failure of Mtb control, including the immune dysregulation induced by the treatment with biological drugs in different autoimmune diseases. Further functional studies, focused on the mechanisms involved in the early host-Mtb interactions and the interplay between host innate and acquired immunity against Mtb, may be helpful to improve the understanding of protective responses in the lung and in the development of novel therapeutic and prophylactic tools in TB.

Biomarkers for risk of developing active tuberculosis in contacts of TB patients: a prospective cohort study

“…Several studies indicate that circulating immune cells are activated and recruited to the M. tuberculosis-infected lungs to form the granuloma where the M. tuberculosis proliferation is controlled by an active interaction of lymphocytes and infected macrophages [15][16][17][18][19][20]. In a previous study, we observed that peripheral white blood cell (WBC) subpopulation ratios varied according to TB clinical status in a limited number of BCG-vaccinated individuals from an area with a high TB burden [17].…”

Biodegradable polylactide microspheres enhance specific immune response induced by Hepatitis B surface antigen

“…9,10 Antigen-specific CTL activity is known to play an essential role in clearing these pathogens. To evaluate the impact of PLA microspheres on antigen-specific CTL activity, we performed 51 Cr release assays.…”

Vaccines against Mycobacterium Tuberculosis: Exploring Alternate Strategies to Combat a Near-perfect Pathogen

“…After fusion has occurred, the infected macrophages and dendritic cells may undergo apoptosis [37], trapping any surviving bacteria in the cell and leaving them vulnerable for further phagocytosis and internalization (and possibly infection) of other cells. Joller et al [38] reviewed the role of phagosome Fc receptors in enhancing the efficacy of fusion and killing intracellular pathogens [39].…”